NAT,
Am I understanding correctly that the studio is now asking you to leave? That's just wrong.
However, I do agree with the sentiment that you should have put a stop to his behaviour much quicker. I do not agree with anyone who advocates violence, but you should have told this person in no uncertain terms that his advances were not wanted and would not be tolerated.
Also, you should initiate action with the studio anytime someone's behavior is making you uncomfortable. Initially, you should simply inform your instructor that the person is making unwanted advances, and ask him/her to document it in your book. If the creep continues, then you should accelerate the action to the studio management, pointing out that this is not the first time. Document your complaint again. If the studio will not support you at this point, then you really should complain to the owner.
Under the circumstances, if they are not going to support you, you should get a full refund of any paid lessons. The studio should not be allowed to apply any contractual accelerations because you got a discount. If they try, a letter from an attorney should quash that attitude, post haste.
If you do manage to stay at this studio, and this idiot won't leave you alone, do not be afraid to raise a major stink. Get loud. Get angry. If it continues further, get legal assistance, because you are in the right.